Removal of organic pollutant (dye) using surface modified Na zeolite: Isotherm and kinetic of dye removal

In this study, zeolite was synthesized and modified using 3-aminopropyl trimethoxy silane. The synthesized materials were identified by FT-IR, SEM, and XRD analyzes and used to separate direct red 80 (DR80) as an organic contaminant from water. The effect of various important factors such as the amount of adsorbent, initial concentration of contaminants and pH was investigated. The results showed that the modified adsorbent had a higher adsorption capacity than the row adsorbent. The amount of dye adsorption is high at lower pH values. The percentage of DR80 dye removal was complete under optimal conditions. Increasing the amount of adsorbent and decreasing the pH increases the percentage of dye removal and increasing the concentration of contaminant reduces the dye removal in the process. The Langmuir, Freundlich and Tempkin isotherm models were used. Isotherm data showed that the adsorption process followed the Langmuir isotherm model. Also, pseodu-first-order, pseodu-second-order and intraparticle diffusion kinetics models were used to investigate the adsorption kinetics. Dye adsorption followed pseodu-second-order kinetics. The results showed that the modified adsorbent could be used as a suitable adsorbent with high adsorption capacity for dye removal from aqueous media.